Extraction of bitumen from oil sands

Abstract

Carbon disulfide is used as a solvent to extract bitumen from oil sands in an anhydrous countercurrent flow process that is compatible with existing procedures for upgrading bitumen. The solution is then treated in a thermal reaction to reduce viscosity and then fractionated to recover the bitumen.

What is claimed is: 
     
       1. A process for the extraction of bitumen from oil sands comprising the steps of:
 (a) contacting the oil sands with carbon disulfide to dissolve the bitumen, and separating solids from the solution; 
 (b) hydrotreating the resulting solution by heating it to a temperature in the range of 200° to 300° C. in the presence of hydrogen; and 
 (c) fractionating the hydrotreated solution to recover bitumen. 
 
     
     
       2. A process as defined in  claim 1  wherein the hydrotreating is conducted in the presence of a catalyst. 
     
     
       3. A process as defined in  claim 2  wherein the catalyst is a cobalt-molybdenum alloy. 
     
     
       4. A process as defined in  claim 1  wherein the step of hydrotreating is characterized by the following formula:
   CS 2 +4H 2 →CH 4 +2H 2 S
 
 
       where CH 4  is methane and H 2 S is hydrogen sulfide.